Punch press safety device



E. Q'WHITE PUNCH PRESS SAFETY DEVICE Fild July 22, 1943 .2 Sheets-Sheet I Oct. 24; 1944. 0. WHITE I 9 5 PUNCH PRESS SAFETY DEVICE Filed Ju ly 22, 1943 Z Sheet S-Sh eer, 2

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I}! l/ /l Z Patented Oct. 24, 1944 UNITED STATES PATENT OFFICE PUNCH PRESS SAFETY DEVICE Emory 0. White, Albertville, Ala. Application July 22, 1943, Serial No. 495,731

Claims.

This invention relates to a safety device for use as an adjunct to punch presses or any other machines, to increase the safety factor.

It is particularly aimed to provide such a device as will prevent operation, as of a foot pedal or other control, unless means are operated by both hands of the operator of the press, and in cases where a gang of presses are simultaneously driven and operated by a plurality of operators, to prevent operation unless means are operated by all hands of all operators.

It is particularly aimed to provide a construction utilizing means to block the operation of a pedal, control, or other part, comprising a plurality of elements adapted to be actuated by different hands, and which are preferably light to the touch'and gravity-operable.

The more specific objects and advantages will become apparent from a consideration of the description following taken in connection with accompany'ing drawings illustrating an operative embodiment.

In said drawings:

Figure 1 is a view in elevation fragmentarily showing the punch press with my improvements in place thereon;

Figure 2 is a side elevation of the parts of Figure 1;

Figure 3 is a longitudinal sectional view through my improvements;-

Figure 4 is a vertical sectional view taken on the plane of line 4-4 of Figure 3;

Figure 5 is a vertical sectional view taken on the plane of line 55 of Figure 3; and

Figure 6 is a fragmentary front elevation of a modified form.

Referring specifically to the drawings wherein like reference characters designate like or similar parts, I0 designates any form of punch press, and the illustration is to be taken accordingly as conventional. At the same time, although a punch press has been shown, it is to be understood that the principles of my invention are applicable to any machine requiring safety control for operation. The particular machine I0 is adapted to be operable through the depression of a lever II at a pedal or tread l2. The particular connection of the pedal or tread l2 and lever II have not been shown, as they constitute no feature of my invention, but on the other hand are conventional.

In carrying out my invention I employ a suitable box or casing at l2 of any particular metal, size, or shape, preferably having separable end walls or closures at l3 and M with inwardly extending flanges or extensions [5 and I5 respectively, extending into opposite ends of the main section I 2' of the casing. Lugs I! and I8 are provided on the end walls 13 and M, for bolting or other attachment as at E9 to the frame of the machine In.

Said end walls l3 and M also have integral therewith bearings as at 29 and 21 inwhich a rockshaft 22 is journaled, the same having integral lugs at 23 for abutment against the end walls l3 and Hi, to prevent longitudinal displacement of such rockshaft. Bearing 2| is somewhat extended, and beyond the same at one end of the rockshaft 22 an arm or crank 2'4 is rigidly connected. A link or rod 25 is pivotally connected to the foot lever I! and the crank 24, and preferably consists of sections adjustably connected together by a turnbuckle 26 of any suitable construction screw-threaded to the sections thereof as shown. I

Rigid on the rockshaft 22 and located substantially centrally in the casing I2 is an upstanding plate or guard 21. Normally disposed in the path of movement of guard 27 with the shaft 22 and from the axis of the latter are detents 28. Such detents are in the form of levers rigid on short pins or shafts 29 journaled in enlargements or outwardly extending pockets 30 on the end plates i3. Only the inner ends of the detents 28 are in the path of movement of the guard 21 when. the detents fall by gravity to such position, for instance, having depending lugs 35 thereon adapted to fasten on lugs 32 carried by a shaft 33 to be referred to later.

Suitable bearings 34 are provided exteriorly on the enlargements 3!] to journal the pins 29, and exterior of the bearings depressible buttons or keys 35 are rigidly carried.

As a result of the construction described the operator of the punch press ID or other machine cannot depress the lever II to operate the machine while the detents 28 are in the path of movement of the guard 21. As a safety feature such operator only can depress the lever ll following depression of the buttons 35, thus requiring the use of both hands, one hand to operate each of them, and which depression of the buttons elevates the detents 28 out of the path of movement of the guard 21, 21 free to rock with the shaft 22 through depression of lever ll, downward movement of rod 25, and rocking of crank 24. Upon release of the buttons 35 by the hands, they as well as the detents 28 will fall immediately by gravity be thereby leaving guard hind the guard 21 to guard against further actuation until the buttons 35 again are depressed.

In some machines where the safety feature of the detents 28 is not desired, the previously mentioned shaft 33 comes into play. Such shaft 33 is journaled in suitable bearings provided in the walls l3 and I4, and at one end exteriorly of the casing has a crank 34 secured thereto as by means of a cotter key 35'. Through the operation or rocking of the crank 34, shaft 33 is turned so that the lugs 32 thereon, through engagement with the lugs 31, will swing detents 28 upwardly out of the path of movement of the guard 21. The shaft 33 and crank 34 are adapted to be secured and locked in either the normal position shown in the drawings or in the position with the detents raised or inutile. To this end an apertured lug 36 is provided on the end wall 14, and openings 31 and 38 are provided in the crank 34. A padlock 39 may be passed through lug 36 and opening 31 to lock the rod 33 in normal position as shown in the drawings, or it can be passed through the lug 3B and opening 38 to lock the rod 33 in its inutile position.

It will be noted that the lower half of the crank 34 is colored red or otherwise as at 40, so as to serve as a signal to the operator, in contrast to the remainder of the crank, when the shaft 33 is in inutile position.

In punch presses or other machines where a plurality of operators are used, I use a safety device as described for each operator, and in such instance adjoin or weld shafts 22 together to require operation by a single operator at a depressible lever I l. Such an arrangement is shown in Figure 6, and the junction of the rods 22 is shown at 22'. It is obvious that a single rod may be used, and it also is clear that before the machine can be operated through depression of the pedal I2, both hands of all operators must be used in depressing the associated buttons 35.

Various changes may be resorted to provided that they fall within the spirit and scope of the invention.

I claim as my invention:

1. Safety mechanism for coaction with an operating means comprising a rock shaft for actuation by said means, a casing in which said shaft is journaled, a guard on the shaft within the easing, and a plurality of detent elements on the casing normally disposed in the path of movement of the guard, said detent elements being displaceable to permit rocking of said shaft, and a shaft supporting the detents in operative position operable simultaneously to displace the detents out of the path of movement of the guard.

2. Safety mechanism for coaction with an operating means comprising a rock shaft for actuation by said means, a casing in which said shaft is journaled, a guard on the shaft within the easing, and a plurality of detent elements on the casing normally disposed in the path of movement of the guard, said detent elements being displaceable to permit rocking of said shaft, and a shaft supporting the detents in operative position operable simultaneously to displace the detents, and means to secure the latter shaft in a position to serve as stops for the detents and in a position maintaining the detents out of the path of movement of the guard inutile.

3. Safety mechanism for coaction with an operating means comprising a rock shaft for actuation by such means, a casing open at its ends, end walls for said casing, said rock shaft being journaled in said end walls, a guard on the rock shaft within the casing, detents pivoted to the end walls and normally disposed behind the guard to prevent actuation of the rock shaft, and means operable to displace the detents.

4. Safety mechanism for coaction with an operating means comprising a rock shaft for actuation by such means, a casing open at its ends, and walls for said casing, said rock shaft being journaled in said end walls, a guard on the rock shaft within the casing, detents pivoted to the end walls and normally disposed behind the guard to prevent actuation of the rock shaft, and means operable to displace the detents, said end walls being detachable, said detents having pins pivoting them to the end walls, and depressible elements connected to the pins to actuate the detents.

5. Safety mechanism for coaction with an operating means comprising a rock shaft for actuation by such means, a casing open at its ends, end walls for said casing, said rock shaft being journaled in said end walls, a guard on the rock shaft within the casing, detents pivoted to the end walls and normally disposed behind the uard to prevent actuation of the rock shaft, and meansoperable to displace the detents, said end walls being detachable, said detents having pins pivoting them to the end walls, and depressible elements connected to the pins to actuate the detents, said end walls having bearings for the rock shaft, said end walls having enlarged portions in which the pins are journaled, a shaft journaled in the end walls having lugs normally serving as stops for the detents, said second-mentioned shaft being operable to displace the detents to enable operation of the rock shaft.

EMORY. O. WI-HTE. 

